Examples of materials and products prepared from polyesters include polyester fiber such as Tetron, alkyd resin for preparing mechanical parts, and unsaturated polyester resin. These polyesters are widely employed in such applications as general-purpose fiber materials, elastic fiber materials, high-strength fiber materials, and plastics.
However, there is a demand for the development of a polyester that exhibits enhanced properties. One example is swimwear. When white swimwear fabricated with conventional Tetron is worn, the body of the wearer can be seen through the swimwear due to the proximity of the refractive index of water and that of Tetron. Meanwhile, swimwear fabricated with a conventional high-refractive-index polyester is disadvantaged by feeling uncomfortable against the skin and by having an unsatisfactory appearance. Thus, there is a demand for a polyester that can provide a fiber satisfying both a high refractive index and having a good sensation against the skin. In addition, conventional polyester has poor biodegradability, and thus a polyester having improved biodegradability is demanded.
In view of the foregoing, an object of the present invention is to provide a polyester having functions such as a high refractive index, high strength, and biodegradability.